Italian authorities are investigating the deaths of at least 23 trafficked Nigerian women on smugglers' boats in the Mediterranean Sea as possible victims of homicide. The International Organization for Migration reports their bodies were found Monday near the Italian port of Salerno.

The International Organization for Migration reports 402 migrants, most from West Africa, were rescued Sunday in four different operations along the central Mediterranean route. It says they, along with the remains of more than 20 women, were brought to the Italian city of Salerno.

In one of the most dramatic operations, the IOM reports a sinking rubber dinghy was found in time to save the lives of 64 people, among the estimated 140 people on board. Among the bodies recovered were those of 23 Nigerian women and girls. The corpses of three other Nigerian women were retrieved from an inflatable boat in another operation.

“What is curious is that they are all from Nigeria, as far as we know. They are all women, a few of them are even under-age women, and we do not have any information or any evidence to discuss now that indicates a homicide. It is just that they, the fact that they all come from one group and it is a group that has been terribly victimized in sex trafficking for the last few years, lends suspicion that there could be a crime involved in their deaths, not just accidental, which is also a crime,” he said.

Millman said the prefect of Salerno has decided to open an investigation to determine the circumstances of the deaths. He said the Italian authorities are performing autopsies on the bodies.

Over the past four days, the IOM reports that rescue operations on the central Mediterranean route saved the lives of more than 2,560 migrants. It said 34 bodies were recovered, with an estimated 50 missing at sea.